This usually happens when some posts have been deleted, for example, if you're showing 20 messages per page, and 23 messages have been posted, that should create 2 pages, right? Now, if I delete 5 of those messages, there are only 18 posts, so only one page. The bug is that the forum doesn't take into account deleted messages (beacuse nothing's really deleted) so it creates 2 pages, even though there's only enough messages for one page. Hence, when you go to the 2nd page, nothing's there.
In the thread you posted, there are supposed to be 89 messages, although there are actually 81 if you count them (7 must have been deleted). The odd thing is, I should be able to see the deleted posts, but for that particular thread, I can't see any.
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